Test media cassette for bodily fluid testing device

ABSTRACT

A bodily fluid sampling device includes a piercing device and a sensor enclosed in a housing. A cassette, which contains test media, is positioned proximal to the sensor so that the sensor is able to analyze a bodily fluid sample collected on the test media. The cassette includes a supply portion from which unused test media is supplied and a storage portion in which contaminated test media is stored after exposure to the bodily fluid. The cassette is adapted to collect a series of bodily fluid samples without requiring disposal of the test media.

REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 12/840,352, filed Jul. 21, 2010. U.S. patent application Ser.No. 12/840,352 is a is a divisional of U.S. patent application Ser. No.11/283,079, filed Nov. 18, 2005, now U.S. Pat. No. 7,785,272. Thepresent application is also a continuation of U.S. patent applicationSer. No. 12/848,282, filed Aug. 2, 2010. U.S. patent application Ser.No. 12/848,282 is a continuation of U.S. patent application Ser. No.11/283,079. U.S. patent application Ser. No. 11/283,079 is acontinuation of U.S. patent application Ser. No. 10/164,828 filed Jun.7, 2002, now U.S. Pat. No. 6,988,996. U.S. patent application Ser. No.10/164,828 claims the benefit of U.S. Provisional Patent Application No.60/296,989, filed Jun. 8, 2001. All of the above-identified patentapplications and patents are incorporated by reference in theirentirety.

BACKGROUND OF THE INVENTION

The present invention relates to bodily fluid sampling devices, and morespecifically, but not exclusively, concerns a bodily fluid samplingdevice that incorporates a test media cassette that contains test mediaused to test bodily fluid.

General Fluid Testing

The acquisition and testing of bodily fluids is useful for manypurposes, and continues to grow in importance for use in medicaldiagnosis and treatment, and in other diverse applications. In themedical field, it is desirable for lay operators to perform testsroutinely, quickly and reproducibly outside of a laboratory setting,with rapid results and a readout of the resulting test information.Testing can be performed on various bodily fluids, and for certainapplications is particularly related to the testing of blood and/orinterstitial fluid. Such fluids can be tested for a variety ofcharacteristics of the fluid, or analytes contained in the fluid, inorder to identify a medical condition, determine therapeutic responses,assess the progress of treatment, and the like.

General Test Steps

The testing of bodily fluids basically involves the steps of obtainingthe fluid sample, transferring the sample to a test device, conducting atest on the fluid sample, and displaying the results. These steps aregenerally performed by a plurality of separate instruments or devices.

Acquiring—Vascular

One method of acquiring the fluid sample involves inserting a hollowneedle or syringe into a vein or artery in order to withdraw a bloodsample. However, such direct vascular blood sampling can have severallimitations, including pain, infection, and hematoma and other bleedingcomplications. In addition, direct vascular blood sampling is notsuitable for repeating on a routine basis, can be extremely difficultand is not advised for patients to perform on themselves.

Acquiring—Incising

The other common technique for collecting a bodily fluid sample is toform an incision in the skin to bring the fluid to the skin surface. Alancet, knife or other cutting instrument is used to form the incisionin the skin. The resulting blood or interstitial fluid specimen is thencollected in a small tube or other container, or is placed directly incontact with a test strip. The fingertip is frequently used as the fluidsource because it is highly vascularized and therefore produces a goodquantity of blood. However, the fingertip also has a large concentrationof nerve endings, and lancing the fingertip can therefore be painful.Alternate sampling sites, such as the palm of the hand, forearm, earlobeand the like, may be useful for sampling, and are less painful. However,they also produce lesser amounts of blood. These alternate sitestherefore are generally appropriate for use only for test systemsrequiring relatively small amounts of fluid, or if steps are taken tofacilitate the expression of the bodily fluid from the incision site.

Various methods and systems for incising the skin are known in the art.Exemplary lancing devices are shown, for example, in U.S. Pat. Nos. Re35,803, issued to Lange, et al. on May 19, 1998.; 4,924,879, issued toO'Brien on May 15, 1990; 5,879,311, issued to Duchon et al. on Feb. 16,1999; 5,857,983, issued to Douglas on Jan. 12, 1999; 6,183,489, issuedto Douglas et al. on Feb. 6, 2001; 6,332,871, issued to Douglas et al.on Dec. 25, 2001; and 5,964,718, issued to Duchon et al. on Oct. 12,1999. A representative commercial lancing device is the Accu-ChekSoftclix lancet.

Expressing

Patients are frequently advised to urge fluid to the incision site, suchas by applying pressure to the area surrounding the incision to milk orpump the fluid from the incision. Mechanical devices are also known tofacilitate the expression of bodily fluid from an incision. Such devicesare shown, for example, in U.S. Pat. Nos. 5,879,311, issued to Duchon etal. on Feb. 16, 1999; 5,857,983, issued to Douglas on Jan. 12, 1999;6,183,489, issued to Douglas et al. on Feb. 6, 2001; 5,951,492, issuedto Douglas et al. on Sep. 14, 1999; 5,951,493, issued to Douglas et al.on Sep. 14, 1999; 5,964,718, issued to Duchon et al. on Oct. 12, 1999;and 6,086,545, issued to Roe et al. on Jul. 11, 2000. A representativecommercial product that promotes the expression of bodily fluid from anincision is the Amira AtLast blood glucose system.

Sampling

The acquisition of the produced bodily fluid, hereafter referred to asthe “sampling” of the fluid, can take various forms. Once the fluidspecimen comes to the skin surface at the incision, a sampling device isplaced into contact with the fluid. Such devices may include, forexample, systems in which a tube or test strip is either locatedadjacent the incision site prior to forming the incision, or is moved tothe incision site shortly after the incision has been formed. A samplingtube may acquire the fluid by suction or by capillary action. Suchsampling systems may include, for example, the systems shown in U.S.Pat. Nos. 6,048,352, issued to Douglas et al. on Apr. 11, 2000;6,099,484, issued to Douglas et al. on Aug. 8, 2000; and 6,332,871,issued to Douglas et al. on Dec. 25, 2001. Examples of commercialsampling devices include the Roche Compact, Amira AtLast, GlucometerElite and Therasense FreeStyle test strips.

Testing General

The bodily fluid sample may be analyzed for a variety of properties orcomponents, as is well known in the art. For example, such analysis maybe directed to hematocrit, blood glucose, coagulation, lead, iron, etc.Testing systems include such means as optical (e.g., reflectance,absorption, fluorescence, Raman, etc.), electrochemical, and magneticmeans for analyzing the sampled fluid. Examples of such test systemsinclude those in U.S. Pat. Nos. 5,824,491, issued to Priest et al. onOct. 20, 1998; 5,962,215, issued to Douglas et al. on Oct. 5, 1999; and5,776,719, issued to Douglas et al. on Jul. 7, 1998.

Typically, a test system takes advantage of a reaction between thebodily fluid to be tested and a reagent present in the test system. Forexample, an optical test strip will generally rely upon a color change,i.e., a change in the wavelength absorbed or reflected by dye formed bythe reagent system used. See, e.g., U.S. Pat. Nos. 3,802,842; 4,061,468;and 4,490,465.

Blood Glucose

A common medical test is the measurement of blood glucose level. Theglucose level can be determined directly by analysis of the blood, orindirectly by analysis of other fluids such as interstitial fluid.Diabetics are generally instructed to measure their blood glucose levelseveral times a day, depending on the nature and severity of theirdiabetes. Based upon the observed pattern in the measured glucoselevels, the patient and physician determine the appropriate level ofinsulin to be administered, also taking into account such issues asdiet, exercise and other factors.

In testing for the presence of an analyte such as glucose in a bodilyfluid, test systems are commonly used which take advantage of anoxidation/reduction reaction which occurs using an oxidase/peroxidasedetection chemistry. The test reagent is exposed to a sample of thebodily fluid for a suitable period of time, and there is a color changeif the analyte (glucose) is present. Typically, the intensity of thischange is proportional to the concentration of analyte in the sample.The color of the reagent is then compared to a known standard whichenables one to determine the amount of analyte present in the sample.This determination can be made, for example, by a visual check or by aninstrument, such as a reflectance spectrophotometer at a selectedwavelength, or a blood glucose meter. Electrochemical and other systemsare also well known for testing bodily fluids for properties onconstituents.

Testing Media

As mentioned above, diabetics typically have to monitor their bloodglucose levels throughout the day so as to ensure that their bloodglucose remains within an acceptable range. Some types sampling devicesrequire the use of testing strips that contain media for absorbingand/or testing the bodily fluid, such as blood. After testing, thetesting media contaminated with blood can be considered a biohazard andneeds to be readily disposed in order to avoid other individuals frombeing exposed to the contaminated test strip. This can be especiallyinconvenient when the person is away from home, such as at restaurant.Moreover, the individual test strips can become easily mixed with othertest strips having different expiration dates. The use of expired teststrips may create false readings, which can result in improper treatmentof the patient, such as improper insulin dosages for diabetics.

SUMMARY OF THE INVENTION

The present invention provides various systems and methods for samplingbodily fluid. The present invention encompasses a bodily fluid samplingdevice that incorporates a cassette containing test media.

In accordance with one aspect of the present invention, there isprovided a bodily fluid sampling device for analyzing a bodily fluid.The sampling device includes a test media cassette that includes a testmedia tape adapted to collect the bodily fluid. The cassette includes asupply portion that stores an uncontaminated section of the test mediatape, which is uncontaminated with the bodily fluid. A storage portionstores a contaminated section of the test media tape that iscontaminated with the bodily fluid. An exposure portion is positionedbetween the supply portion and the storage portion. The exposure portionis adapted to expose a section of the test media tape to the bodilyfluid. A sensor is positioned between the supply portion and the storageportion to sense at least one property of the bodily fluid collected onthe test media tape at the exposure portion of the cassette.

Another aspect of the present invention concerns a test cassette forcollecting a bodily fluid sample. The cassette includes a test mediatape, which has a contaminated section that is contaminated with pastsamples of the bodily fluid and an uncontaminated section. The cassetteincludes a housing that has a supply portion in which the uncontaminatedsection of the test media tape is enclosed. The housing further includesa storage portion in which the contaminated section of the test mediatape is enclosed. The housing defines an exposure opening along the testmedia tape at which the test media tape is exposed to the bodily fluid.A supply reel is disposed in the supply portion of the housing aroundwhich the uncontaminated section of the test media tape is wrapped. Astorage reel is disposed in the storage portion of the housing aroundwhich the contaminated section of the test media tape is wrapped.

Other forms, embodiments, objects, features, advantages, benefits andaspects of the present invention shall become apparent from the detaileddrawings and description contained herein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial, cross-sectional view of a bodily fluid samplingdevice according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view of a test cassette and sensor used inthe FIG. 1 sampling device.

FIG. 3 is a partial, side view of the FIG. 2 cassette.

FIG. 4 is a cross-sectional view of the FIG. 1 sampling device.

FIG. 5 is a front view of an indexing mechanism used in the FIG. 1sampling device.

FIG. 6 is a cross-sectional view of a test cassette according to anotherembodiment of the present invention.

FIG. 7 is a cross-sectional view of a bodily fluid sampling deviceaccording to another embodiment of the present invention.

FIG. 8 is a front view of test media used in the FIG. 7 sampling device.

FIG. 9 is a side view of the FIG. 8 test media.

FIG. 10 is a side view of the FIG. 8 test media with a piercing devicefrom the FIG. 7 sampling device.

FIG. 11 is a cross-sectional view of a bodily fluid sampling deviceaccording to another embodiment of the present invention.

FIG. 12 is a diagrammatic view of a sensor system according to anotherembodiment of the present invention.

FIG. 13 is a cross-sectional view of a bodily fluid testing systemaccording to another embodiment of the present invention.

FIG. 14 is a cross-sectional view of test media used in the FIG. 13sampling device.

FIG. 15 is an enlarged, cross-sectional view of a portion of the FIG. 14test media.

DESCRIPTION OF SELECTED EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications in the illustrated device, and such further applicationsof the principles of the invention as illustrated therein beingcontemplated as would normally occur to one skilled in the art to whichthe invention relates. One embodiment of the invention is shown in greatdetail, although it will be apparent to those skilled in the art thatsome of the features which are not relevant to the invention may not beshown for the sake of clarity.

The present invention concerns a bodily fluid sampling device thatincorporates a test cassette. The cassette houses test media that isused to collect bodily fluid samples which are analyzed with a sensor inthe sampling device. The test media in the cassette is indexed before orafter each test so that successive tests can be performed withoutrequiring disposal of the used test media. The test media can be indexedmanually or automatically. In one aspect of the present invention, thetest media includes a cover tape that protects the test media beforetesting. In another aspect, the test media defines one or morepassageways through which a piercing device is able to pass through inorder to pierce the skin of a user. The cassette, in another aspect ofthe present invention, is designed for use with a vacuum-style samplingdevice in which the bodily fluid sample is drawn to the test media by avacuum.

A bodily fluid sampling device 30 according to one embodiment of thepresent invention is illustrated in FIGS. 1-5. As shown in FIGS. 1 and4, the sampling device 30 includes a housing 32 with a piercing endportion 34 and an opposite, sampling end portion 36. The piercingportion 34 of the housing 32 is slidable relative to the samplingportion 36. As shown in FIG. 4, piercing portion 34 defines a piercingdevice cavity 38 with a piercing device opening 40. In the piercingcavity 38, a piercing device or member 42, which is used for puncturingskin, is covered by the piercing portion 34 of the housing 32 to avoidaccidental piercing of the skin. The piercing device 42 cuts an incisionin the skin such that the bodily fluid, such as blood, pools on thesurface of the skin. In one embodiment, the piercing device 42 includesa lancet suitable to puncture the cutaneous layer of the skin. As shouldbe appreciated, other types of piercing devices 42 can also be used,such as needles and blades, to name a few.

As illustrated in FIG. 4, the piercing portion 34 of the housing 32 isslidably received on a slide member 44 that extends from the samplingportion 36 of the housing 32. The piercing device 42 is removablycoupled to the slide member 44. A spring 46 on the slide member 44biases the piercing portion 34 of the housing 32 away from the samplingportion 36, and a stop member 48 on the slide member 44 prevents thepiercing portion 34 from sliding off the slide member 44. Normally, thepiercing portion 34 of the housing 32 covers the piercing device 42.Once the piercing portion 34 is pressed against the skin, the piercingportion 34 retracts towards the sampling portion 36 of the housing 32 toexpose the piercing device 42 through opening 40. In the illustratedembodiment, the piercing portion 34 of the housing 32 has a compressionring 50 around opening 40 in order to draw the bodily fluid to thesurface of the skin. In one form, the compression ring 50 is clear sothat the user can view the pooling of the bodily fluid.

Referring to FIG. 1, the bodily fluid sampling device 30 includes asampling system 52 for sampling and testing the drawn bodily fluid. Asshown, the sampling system 52 includes a test cassette 54 and a sensor56. In one embodiment, the sensor 56 is an optical sensor that includesa light source and a detector for determining the amount of lightreflected from the collected sample. It should be appreciated, however,that other types of sensors 56 can be used to monitor analyte levels inbodily fluid. For example, the sensor 56 can include an electrical typesensor that measures the electrical and/or electrochemical properties ofthe sample. The sampling portion 36 of the housing 32 defines a bodilyfluid acquisition opening 58 through which the bodily fluid is suppliedto the cassette 54. In one embodiment, the cassette 54 is removablycoupled to the sampling device 30 such that the cassette 54 can bereplaced with a new one. A pivotal cover 60 is pivotally mounted to thehousing 32. The cover 60 can be opened to allow disposal and replacementof the cassette 54.

As shown in greater detail in FIGS. 2 and 3, the cassette 54 has anouter casing 62 that encloses test media 64. In the illustratedembodiment, the test media 64 is in the form of a continuous strip ortape. As will be appreciated, the test media 64 can be further segmentedinto discrete test sections. The casing 62 of the cassette 54 defines anunexposed test media supply portion 66, which stores unused test media64, and an exposed test media storage portion 68, which stores used testmedia 64. Connecting together the unexposed 66 and exposed 68 mediaportions, an exposure/testing portion 70 is configured to allow thebodily fluid to be collected and tested on the test media 64. As shown,the testing portion 70 has outboard sidewall 72 and an opposite, inboardsidewall 74. On the outboard sidewall 72 of the cassette 54, the casing62 defines an exposure opening 76 at which the test media 64 is exposedto the bodily fluid. Opposite the exposure opening 76, the inboardsidewall 74 of the casing 62 defines a test opening 78 at which thesensor 56 is able to analyze the bodily fluid collected on the testmedia 64. In the illustrated embodiment, the exposure 76 and test 78openings are aligned with another. In other embodiments, openings 76 and78 can be instead offset from one another. For instance, the testingopening 78 can be located closer towards the exposed media storageportion 68, as compared to exposure opening 76.

In the unexposed media storage portion 66 of the cassette 54, a supplyreel 80 is rotatably mounted, and unused test media 64 is wrapped aroundthe supply reel 80. Similarly, the exposed media storage portion 68 hasa take-up reel 82 rotatably mounted inside. Test media 64 that has beenexposed to the bodily fluid at the exposure opening 76 is wrapped aroundthe take-up reel 82. It should be appreciated that in other embodiments,one or both of the reels 80, 82 can be omitted from the cassette 54.Both reels 80 and 82 define drive cavities 84 that can be engaged withdrive members 86 in the sampling end portion 36 of the sampling device30 (FIG. 4). As shown in FIGS. 2 and 4, the drive cavities 84 havenotches 88 that mate with flanges 90 on the drive members 86 such thatthe drive members 86 are able to rotate the reels 80 and 82. To ensurethat the used test media 54 is not removed from the exposed mediastorage portion 68 of the cassette 54, the take-up reel 82 has a gearedportion 92 that engages a biased, cassette pawl 94 that permits thetake-up reel 82 to rotate in only one direction. This ensures that thetest media 64 can only be fed into exposed media storage portion 68 andnot removed.

As shown in FIGS. 4 and 5, the sampling device 30 further incorporatesan advancement or indexing device 96 that advances the test media 64 inthe cassette 54 such that fresh test media 54 is available every time abodily fluid sample is taken. In the illustrated embodiment, amechanical type advancement device 96 is used to advance the test media64. However, it should be appreciated that an electrical or acombination electro-mechanical type advancement device 96 may also beused. In FIG. 4, the advancement device 96 includes a rack member 98that is attached to the piercing portion 34 of the housing 32. The rackmember 98 extends from the piercing portion 34 and terminates proximalto take-up drive member 100. The take-up drive member 100 is constructedto engage and rotate the take-up reel 82 in the cassette 54. The rackmember 98 has rack teeth 102 that engage take-up drive teeth 104 on thetake-up drive member 100. To ensure that the take-up drive member 100only rotates in one direction, the advancement device 96 has anadvancement pawl 106 attached to the housing 32 and biased against thetake-up drive teeth 104. As shown in FIG. 5, both teeth 102 and 104 areangled in such a manner to only firmly engage one another when rotatingthe take-up drive member 100 in a counter-clockwise fashion (from theperspective of FIG. 5). In the illustrated embodiment, only the take-updrive member 100 is powered, while supply drive member 108 is able tofreely rotate. In other embodiments, both drive members 100 and 108 maybe powered individually or together. For instance, when anelectro-mechanical type advancement device 96 is used, both drivemembers 100 and 108 can be individually powered by separate electricmotors.

Referring again to FIG. 1, the bodily fluid sampling device 30 furtherincludes a test indicator 110, a display 112, at least one controlbutton 114, and a grip portion 116. In the illustrated embodiment, thegrip portion 116 has ridges that help ensure the user has a firm grip onthe sampling device 30. The test indicator 110 can either indicate thenumber of tests performed or the number of tests remaining on thecurrent cassette 54. The housing 32 has an indicator window 118 throughwhich the indicator 110 can be viewed. The display 112 is operativelycoupled to the sensor 56 and displays readings from the sensor 56. Thebutton 114 is used to control and enter information into the bodilyfluid sampling device 30. In the illustrated embodiment, the indicator110 and the display 112 are separate components. However, it should beappreciated that the indicator 110 can be incorporated into the display112 to form a single unit.

A detailed view of a test indicator assembly 120, which moves theindicator 110, according to one embodiment of the present invention isillustrated in FIG. 5. As shown, the take-up drive member 100 has a gear122 that engages an intermediate gear 124. The intermediate gear 124engages an indicator gear 126 that is attached to the indicator 110. Theindicator 110 has numbering 128, or other types of characters, thatindicates the number of samples taken with the cassette 54 or the numberof tests remaining on the cassette 54. As the take-up drive member 100is rotated by the rack member 98, the intermediate gear 124 rotates,which in turn rotates the indicator. Although in the illustratedembodiment of the test indicator assembly 120 is mechanically driven, itshould be appreciated that the indicator 110 can be operated in othermanners, such as electronically.

In operation, the user presses opening 40 of the piercing portion 34against the skin. The piercing portion 34 of the housing 32 retractstowards the sampling portion 36 exposing the piercing device 42 so as topierce the skin. As the piercing portion 34 retracts, the rack member 98rotates the take-up drive 100 in order to advance the test media 64 inthe cassette 54 such that unused test media 64 is available for testing.Once the user creates a bodily fluid sample with the piercing device 42,the user places opening 58 over the bodily fluid sample. A portion ofthe bodily fluid sample travels via direct or capillary action to theunused test media 64 exposed at exposure opening 76 of the cassette 54.When a portion of the bodily fluid sample deposits on the test media 64,the sensor 56 determines the amount of analyte material in the sample.The readings from the sensor 56 are shown on the display 112. During thenext test, the cassette 54 is indexed in response to pressing thesampling device 30 against the skin so as to move the contaminatedportion of the test media 64 into the storage portion 68 of the cassette54. As should be appreciated, the sampling device 30 can be insteadconfigured to advance the test media 64 after the bodily fluid samplehas been collected or analyzed.

As should be appreciated, the cassette 54 allows a user to perform anumber of tests without replacing the test media 64. Once the test media64 has been completely used, the contaminated test media 64 in thecassette 54 can be safely discarded. In one embodiment, the cassette 54allows the user to perform a number of tests within a range from aboutfive (5) tests to about five-hundred (500) tests. In another embodiment,the cassette 54 is adapted to perform five (5) to fifty (50) testsbefore being replaced, and in a further embodiment, the cassette 54 isdesigned to perform around twenty-five (25) tests. With the abovedescribed configuration, the cassette 54 according to the presentinvention minimizes the amount of biohazard material generated aftereach test because a test strip does not have to be discarded after eachtest. Further, since test strips do not have to be individually insertedand removed during each test, the ease of use and convenience isimproved with the cassette 54 according to the present invention.Moreover, the cassette 54 obviates the need for the user to carry a vilecontaining the test strips.

A cassette 54 a according to another embodiment of the present inventionis illustrated in FIG. 6. As shown, the cassette 54 a has an outer cover60 a with an unexposed media supply portion 66 a, an exposed mediastorage portion 68 a, and an exposure/testing portion 70 a. The exposedportion 68 a of the cover 60 a houses a take-up reel 82 a, while theunexposed portion 66 a houses a supply reel 80 a. The test media 64 aextends between and is wrapped around both the supply reel 80 a and thetake-up reel 82 a. In the illustrated embodiment, the test media 64 ahas a cover tape 130 that covers a test tape 132. The cover tape 130provides an airtight seal over the test tape 132 in order to preservetest chemicals on the test tape 132 while the sampling device 30 is notin use. As illustrated, the cassette 54 a further includes a peel tab134, a cover reel 136 and guides 138 to guide the test media 64 abetween reels 80 a and 82 a. The peel tab 134 along with the cover reel136 are configured to peel the cover tape 130 from the test tape 132. Tosynchronize rotation of the supply reel 80 a and the cover reel 136, thesupply reel 80 a and the cover reel 136 respectively have a supply gear140 and a cover gear 142 that are intermeshed with one another. Inanother embodiment, the rotation of the cover reel 136 is synchronizedwith the take-up reel 82 a.

During use, as the take-up reel 82 a is indexed by the sampling device30, both the supply reel 80 a and the cover reel 136 are rotated inunison through gears 140 and 142. As the cover reel 136 rotates, thetension formed on the cover tape 130 between the cover reel 136 and thepeel tab 134 causes the cover tape 130 to be pulled from the test tape132 at the peel tab 134. The peeled cover tape 130 is wrapped around andstored on the cover reel 136. After the cover tape 130 is removed, thetest tape 132 is exposed to the bodily fluid sample at an exposureopening 76 a formed in the cover 60 a. The now exposed test tape 132 canbe tested at testing opening 78 a that is incorporated into the exposureopening 76 a. During the next index of the cassette 54 a, the used testtape 132 is wrapped around and stored on the take-up reel 82 a.

A bodily fluid sampling device 144 according to another embodiment ofthe present invention is illustrated in FIG. 7. The sampling device 144includes a cassette 54 b and a pivot arm 146 with a pivot end 148pivotally mounted to the cassette 54 b. Opposite the pivot end 148, atfree end 150, the pivot arm 146 is coupled to piercing device 42. Aspring 152 mounted between the cassette 54 b and the pivot arm 146biases the free end 150 of the pivot arm 146 to move towards thecassette 54 b in the direction indicated by arrow A in FIG. 7. A releasemechanism 154 is coupled to the free end 150 of the pivot arm 146 inorder to bias the piercing device 42 away from the cassette 54 b. Thecassette 54 b includes a supply reel 80, a take-up reel 82 and a testmedia 64 b extending between and wrapped around both reels 80, 82. Asillustrated, housing 156 of the sampling device 144 defines a sampleopening 158 through which the bodily fluid sample is collected. The testmedia 64 b of the cassette 54 is positioned over the sample opening 158between the opening 158 and the piercing device 42.

As shown in further detail in FIGS. 8, 9 and 10, the test media 64 b inthis embodiment includes a number of test pads 160 spaced apart from oneanother along the test media 64 b. In one embodiment, the test pads 160contain chemicals reactive to specific constituents contained in thebodily fluid. In one form, the test pad 160 includes a chemistry padavailable in an AT LAST™ Blood Glucose System available from AmiraMedical located in Scotts Valley, Calif. In another embodiment, thebodily fluid sample is collected on the test pad 160 for electricaland/or optical analysis. Over each test pad 160, the test media 64 b hasa blister pack 162 that is used to draw the bodily fluid throughcapillary action onto the test pad 160. During indexing of the testmedia 64 b, a capillary opening 163 (FIG. 8), such as a slit or hole, iscut or pierced into the blister pack 162 by a cutting device, such asrazor, in the fluid sampling device 144. In the illustrated embodiment,the opening 163 is in the form of a slit. The capillary slit 163 is usedto draw the bodily fluid into the blister pack 162 through capillaryaction. In the illustrated embodiment the blister pack 162 has acircular shape that fits inside the rectangularly shaped test pad 160such that portions of the test pad 160 extend past the blister pack 164.In one form, the blister pack 164 is a plastic film covering the testpad 160 and attached to the test media 64 b through an adhesive and/orheat sealing. Moreover, in one embodiment, the test media 64 b istransparent or semitransparent to allow optical analysis of the bodilyfluid. As illustrated in FIGS. 9 and 10 each blister pack 162 has aconvex surface 164 that aids in drawing the fluid up to the test pad 160through the slit 163 via capillary action. To be near the skin in orderto collect bodily fluid, both the test pad 160 and the blister pack 162are positioned on the outboard side 170 of the test media 64 b. Inanother embodiment, the blister pack 162 is omitted such that the bodilyfluid directly contacts the test pad 160 during collection of the bodilyfluid. Between each test pad 160, the test media 64 b defines a piercingdevice hole or throughway 166. The piercing device throughway 166extends from inboard side 168 to outboard side 170 of the test media 64b. The throughway 166 is sized such that the piercing device 42 is ableto extend through the test media 64 b in order to pierce the skin. Inanother embodiment, the test media 64 b is designed to be pierced by thepiercing device 42 such that the throughway 166 is not required.

During testing, the user places sample opening 158 of the samplingdevice 144 against his or her skin 172 (FIGS. 7 and 10). Next, the userdisengages the release 154 such that the piercing device 42 on thepivotal arm 146 moves toward the test media 64 b. As the pivot arm 146rotates, the piercing device 42 extends through the throughway 166 andpierces the skin 172 (FIG. 10). After piercing the skin 172, thepiercing device 42 retracts away from the skin 172 and out of thethroughway 166. In one embodiment, the piercing device 42 is retractedthrough recoil of a firing spring that is used to initially advance thepiercing device 42 to lance the skin 172. At the site where the skin 172was pierced, the bodily fluid collects and is drawn up by the slit 163in the blister pack 162 to the test pad 160 via capillary action. Tostore used test media 64 b on the take-up reel 82, the test media 64 bin the cassette 54 b can be advanced mechanically or manually before orafter a test is performed. In one embodiment, the test media 64 b in thecassette automatically advances when the pivot arm 146 swings toward thecassette 54 b. In another embodiment, the test media 64 b is advancedmanually after the sample has been collected and tested.

A bodily fluid sampling device 174 according to another embodiment ofthe present invention is illustrated in FIG. 11. The sampling device 174has a piercing device 42 coupled to a pivot arm 146 that is pivotallycoupled to a trigger mechanism 176. Both the pivot arm 146 and thetrigger mechanism 176 of the sampling device 174 are pivotally coupledto a housing 178. The housing 178 defines a sample opening 158. Thepivot arm 146 and the piercing device 42 are positioned within thehousing 178 such that the piercing device 42 is able to swing throughthe opening 158 and pierce the skin. The sampling device 174 furtherincludes a cassette-sensor assembly 180 pivotally mounted to the housing178 through a swing arm 182. As shown, the cassette-sensor assembly 180includes a cassette 54 and a sensor 56. The sensor 56 is mountedproximal to and in a fixed relationship with the cassette 54 throughmounting arms 184. The swing arm 182 of the cassette-sensor assembly 180can be moved by a number ways. In one embodiment, the swing arm 182 isactuated through a mechanical linkage with the trigger mechanism 176,and in another embodiment, the swing arm 182 is moved by an electricmotor.

To take and test a bodily fluid sample, the user presses the sampleopening 158 against the skin of the user. The user then cocks thetrigger mechanism 176 and releases the trigger mechanism 176 in order toswing the piercing device 42 through the sample opening 158 to piercethe skin of the user. Afterwards, the piercing device 42 retracts backinto the housing 178 as a sample of the bodily fluid, such as blood,collects on the skin. In one form, the piercing device 42 is retractedby the recoil of a firing spring that is initially used to lance theskin. To collect and test the bodily fluid sample, the swing arm 182swings the cassette sensor assembly 180 over the opening 158. After thesample is deposited on the test media 64 in the cassette 54, the sensor56 analyzes the collected sample. In one form, the sensor 56 is anoptical type sensor that analyzes the optical properties of the sample.In another form, the sensor 56 analyzes the electrical properties of thesample.

As mentioned above, the sensor 56 can analyze the bodily fluid sample byusing a number of techniques. In one embodiment, the sensor 56 analyzesthe electrochemical properties of the sample. In another embodiment thatis illustrated in FIG. 12, the sensor 56 includes an optical sensorsystem 186 that remotely detects the optical properties of the sampledbodily fluid. The optical sensor system 186 includes a remotely locatedlight source/detector 188, which can be located inside or outside of thebodily fluid sampling device. The light source/detector 188 employscomponents suitable for emitting light and for determining the amountand/or frequency of reflected light. By way of nonlimiting example, thelight source/detector 188 can include a light emitting diode (LED), aphotodiode and the like. With such a construction, the optical sensorsystem 186 according to the present invention allows for more compactsampling device and cassette designs. As shown, a pair of fiber opticcables 190 are coupled to the light source/detector 188. The fiber opticcables 190 include a transmission cable 192 and a detection cable 194.The fiber optic cables 190 extend from the light source/detector 188 toa test area 196 that is proximal the test media 64. In the test area196, the transmission cable 192 is coupled to an emitter 198 that isadapted to emit light, and the detection cable 194 is coupled to adetector 200 that is adapted to receive light.

During testing, after the bodily fluid sample has been placed on thetest media 64, the light source/detector 188 emits light from theemitter 198 via transmission cable 192. The light emitted from theemitter 198 is reflected off the bodily fluid sample on the test media64, and the reflected light is detected by the light source/detector 188via the detector 200. The light/source detector 188 analyzes the amountand/or frequency of the light reflected from the bodily fluid sample inorder to determine the amount of analyte in the sample. As used hereinand in conventional fashion, reference to analysis of the bodily fluidalso includes analysis of the results of a reaction of a selectedreagent with the bodily fluid.

A bodily fluid testing system 202 that can be integrated into a samplingdevice according to the present invention is illustrated in FIG. 13. Thetesting system 202 includes a vacuum assembly 204, a piercing assembly206, a sensor 56, and test media 64 c. In the illustrated embodiment,the test media 64 c is not housed in a cassette case. Rather, the testmedia 64 c is wrapped around and extends between supply reel 80 andtake-up reel 82. It should be appreciated that the test media 64 c canbe encased in a cassette case. As shown, the test media 64 c has aninboard side 208 and an opposite, outboard side 210. The vacuum assembly204, the piercing assembly 206 and the sensor 56 are positioned alongthe test media 64 c between the supply reel 80 and the take-up reel 82.In particular, both the vacuum assembly 204 and the sensor 56 arepositioned on the inboard side 208, with the sensor 56 positionedbetween the take-up reel 82 and the vacuum assembly 204. The piercingassembly 206 is disposed opposite the vacuum assembly 204 on theoutboard side 210 of the test media 64 c.

The vacuum assembly 204 is adapted to generate a vacuum in order to drawa bodily fluid sample onto and/or into the test media 64 c. The vacuumassembly 204 can include, but is not limited to, a pre-charge vacuumdevice, an electromagnetic diaphragm vacuum device and/or a mechanicalvacuum device, to name a few. In the illustrated embodiment, the vacuumassembly 204 has a body 212 that defines a vacuum cavity 214. Near thetest media 64 c, the body 212 defines a vacuum port 216 that opens intothe vacuum cavity 214. A piston 218 is slidably received in the vacuumcavity 214. Solenoids 220 are used to actuate the piston 218 in order toform a vacuum in the vacuum cavity 214.

As shown in FIG. 13, the piercing assembly 206 includes a piercingdevice 42 a, a holder 222, which holds the piercing device 42 a, and aprotective cover 224. In the illustrated embodiment, the piercing device42 a has a distal tip 226 adapted to pierce the skin of the user and aproximal tip 228. As depicted in FIG. 15, the piercing device 42 adefines a cavity 227 that extends from the distal tip 226 to theproximal tip 228. The cavity 227 transports bodily fluid from the userto the test media 64 c. Referring again to FIG. 13, the protective cover224 covers the distal tip 226 of the piercing device 42 a so as toprevent a person from being accidentally cut with the piercing device 42a. The holder 222 includes a coil spring 230 wrapped around the piercingdevice 42 a such that the piercing device 42 a is able to be removed andreplaced with another piercing device 42 a. As shown, the holder 222 hasa hollow, inner holder member 232 that is surrounded by an outer holdermember 234. The piercing device 42 a along with the coil spring 230 arereceived inside the inner holder member 232. To prevent over-penetrationof the proximal tip 228 of the piercing device 42 a into the test media64 c during testing, the inner holder member 232 has a stop ridge 236that engages the piercing device 42 a. The holder 222 further includes acollapsible, biasing member 238 that normally biases the piercing device42 a away from the test media 64 c. When the holder 222 is pressedagainst the skin during piercing, the biasing member 238 collapses suchthat the proximal tip 228 of the piercing device 42 a is able to piercethe test media 64 c.

As illustrated in FIGS. 14 and 15, the test media 64 c has a number oftesting sections 240 that are adapted to collect separate bodily fluidsamples. Each testing section 240 has a test pad 242 positioned betweena seal membrane 244 and a vacuum passageway 246 that is defined in thetest media 64 c. In one embodiment, the test pad 242 is embedded withchemicals that are reactive with specific bodily fluid constituents fortesting purposes. In another embodiment, the test pad 242 is adapted tocollect and absorb the bodily fluid sample for analysis by the sensor56. On the outboard side 210 of the test media 64 c, the seal membrane244 seals over the test membrane 242. On the inboard side 208, thevacuum passageway 246 is adapted to align with the vacuum port 216 ofthe vacuum assembly 204 such that the vacuum assembly 204 is able toform a vacuum (an area of low pressure) in the vacuum passageway 246 andaround the test pad 242. The seal 244 is made of suitable material thatallows the vacuum to be maintained around the test pad 242, while at thesame time being able to be punctured by the piercing device 42 a (FIG.15). The seal 244 may be formed from various types of sealing materials,such as rubber and/or silicone, to name a few.

As mentioned above, to test a bodily fluid sample, the user presses theholder 222 against the skin in order to pierce the skin with thepiercing device 42 a. As piercing device 42 a pierces the skin, thebiasing member 238 collapses to allow the proximal tip 228 to puncturethe test media 64 c. As shown in FIG. 15, the seal 244 is punctured byand seals around the proximal tip 228. The vacuum assembly 204 forms avacuum in the vacuum passageway in order to draw the bodily fluid sampleonto the test pad 242. Once the sample is collected on the test pad 242,the holder 22 is removed from the skin and the vacuum assembly 204ceases operation. The test pad 242 is then indexed proximal to thesensor 56 for analysis.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiment has been shown and described and that allchanges and modifications that come within the spirit of the inventionare desired to be protected.

1. An apparatus, comprising: a cassette including test media tapeconfigured to collect body fluid; and a sensor configured to analyze thebody fluid collected by the test media tape using an optical technique,the sensor including a light source/detector located remotely from thetest media tape, and optical fibers extending from the lightsource/detector to a test area that is proximal to the test media tape.2. The apparatus of claim 1, wherein the optical fibers include: atransmission optical fiber extending from the light source/detector tothe test area, the transmission optical fiber being configured totransmit light from the light source/detector to the test area; and adetection optical fiber extending from the light source/detector to thetest area, the detection optical fiber being configured to transmit thelight reflected from the body fluid on the test media tape to the lightsource/detector.
 3. The apparatus of claim 2, further comprising: anemitter coupled to the transmission optical fiber, the emitter beingconfigured to emit the light from the transmission optical fiber; and adetector coupled to the detection optical fiber, the detector beingconfigured to receive the light reflected from the test media tape. 4.The apparatus of claim 3, wherein the light source/detector includes alight emitting diode.
 5. The apparatus of claim 3, wherein the lightsource/detector includes a photodiode.
 6. The apparatus of claim 1,wherein the optical fibers include a transmission optical fiberextending from the light source/detector to the test area.
 7. Theapparatus of claim 1, wherein the optical fibers include a detectionoptical fiber extending from the light source/detector to the test area.8. The apparatus of claim 1, wherein the sensor and the cassette areincorporated into a body fluid sampling device.
 9. An apparatus,comprising: a sensor configured to analyze body fluid collected by atest media, the sensor including a detector located at a position thatis remote from the test media, wherein the detector is configured toanalyze the body fluid collected by the test media using an opticaltechnique, and a detection optical fiber extending from the detector tothe test media, the detection optical fiber being configured to transmitlight from the test media to the detector.
 10. The apparatus of claim 9,wherein the sensor includes: a light source incorporated with thedetector; and a transmission optical fiber extending from the lightsource to the test media, the transmission optical fiber beingconfigured to transmit light from the light source to the test media.11. The apparatus of claim 10, further comprising: an emitter coupled tothe transmission optical fiber, the emitter being configured to emit thelight from the transmission optical fiber; and a detector coupled to thedetection optical fiber, the detector being configured to receive thelight reflected from the test media.
 12. The apparatus of claim 9,further comprising: a detector coupled to the detection optical fiber,the detector being configured to receive the light reflected from thetest media.
 13. The apparatus of claim 9, further comprising: a cassettein which the test media is stored in the form of a test media tape. 14.An apparatus, comprising: a sensor configured to analyze body fluidcollected by a test media, the sensor including a light source locatedat a position that is remote from the test media, and a transmissionoptical fiber extending from the light source to the test media, thetransmission optical fiber being configured to transmit light from thelight source to the test media.
 15. The apparatus of claim 14, furthercomprising: a detector incorporated with the light source; and adetection optical fiber extending from the detector to the test media,the detection optical fiber being configured to transmit light from thetest media to the detector.
 16. The apparatus of claim 14, furthercomprising: an emitter coupled to the transmission optical fiber, theemitter being configured to emit the light from the transmission opticalfiber.
 17. The apparatus of claim 14, further comprising: a cassette inwhich the test media is stored in the form of a test media tape.
 18. Amethod, comprising: transmitting light from a light source/detector viaa transmission optical fiber, wherein the transmission optical fiber iscoupled to an emitter; emitting the light from the emitter towards atest media with a body fluid; receiving the light reflected from bodyfluid on the test media with a detector; transmitting the light from thedetector to the light source/detector via a detection fiber optic cable;and determining an amount of analyte in the body fluid by measuring withthe light source/detector a property of the light reflected from thebody fluid on the test media.
 19. The method of claim 18, wherein saiddetermining includes analyzing the frequency of the light reflected fromthe body fluid on the test media.
 20. The method of claim 18, whereinthe test media is in the form of a test media tape housed in a cassette.